<!DOCTYPE html>
<html>

	<head>
		<meta charset="UTF-8">
		<title></title>
		<style type="text/css">
			.p1 {
				font-size: 50px;
				color: red;
			}
			.p2 {
				color: red;
				text-decoration: underline;
			}
			.p3 {
				font-size: 50px;
				text-decoration: underline;
			}
			.p4{
				font-size: 50px;
				text-decoration: underline;
				color: red;
			}
		</style>
	</head>

	<body>
		<p class="p1">段落1</p>
		<p class="p2">段落2</p>
		<p class="p3">段落3</p>
		<p class="p4">段落4</p>
	</body>

</html>